JP7021998B2 - Water-soluble processing oil for fixed-abrasive wire saws, processing liquid for fixed-abrasive wire saws, cutting processing methods and used processing liquid processing methods - Google Patents

Description

The present invention relates to a water-soluble processing oil for a fixed-abrasive wire saw used for cutting a brittle material with a fixed-abrasive wire saw, a processing liquid for a fixed-abrasive wire saw, a cutting method, and a used processing liquid processing method. Is.

Conventionally, as disclosed in Patent Document 1, in cutting of a brittle material with a fixed-abrasive wire saw, a processing liquid for a fixed-abrasive wire saw (hereinafter, also simply referred to as "processing liquid") is used for cooling, lubrication, and the like. .) Is used. As the processing liquid, a water-soluble processing oil for fixed-abrasive wire saws (hereinafter, also simply referred to as “processing oil”), which is an undiluted solution, is diluted with water about 5 to 50 times. Further, the processing liquid is collected and reused after processing in order to reduce the cost.

Japanese Unexamined Patent Publication No. 2015-139861

In recent years, each slice maker has been thinning wires in order to reduce chips (carfloss) generated during cutting. Therefore, from the viewpoint of preventing wire breakage, it has been attempted to use a processing liquid obtained by highly diluting the processing oil with water (for example, diluting it 100 times or more) for the purpose of improving the cooling property. However, none of the conventional processing oils have properties such as lubricity required at the time of cutting when highly diluted with water in this way.

In addition, when using a processing liquid in which the processing oil is highly diluted with water, the concentration of the processing oil component in the processing liquid is extremely low, so it is possible to accurately measure how much the processing oil component has disappeared after use. Have difficulty. Therefore, the used processing liquid is discarded without being reused. At this time, it is not easy to purify the used processing liquid to the extent that it meets the sewage exclusion standard stipulated by law, and it cannot be drained to the sewer. Therefore, the used processing liquid is disposed of as industrial waste, resulting in high disposal cost.

The present invention has the properties required for cutting, and is a water-soluble processing oil for fixed-abrasive wire saws and a processing liquid for fixed-abrasive wire saws that can purify used processing liquids by a simple purification process. It is an object of the present invention to provide a cutting processing method and a used processing liquid treatment method.

The water-soluble processing oil for a fixed-abrasive wire saw of the present invention contains the compound (A) represented by the formula (1) and is diluted with water so that the concentration of the compound (A) is 700 ppm or more and 3000 ppm or less on a mass basis. It is characterized in that it is used for cutting brittle materials with a fixed abrasive grain wire saw.
RO-[(EO) _m (PO) _n ] -H (1)
(In the formula (1), R represents an alkyl group having 8 or more carbon atoms and 12 or less carbon atoms, EO represents an oxyethylene group, PO represents an oxypropylene group, m represents the average number of moles of EO added, and n is. The average number of moles of PO added is shown, m is a number of 2 or more and 5 or less, n is a number of 3 or more and 5 or less, and EO and PO may be random addition or block addition).

According to this configuration, a processing liquid obtained by diluting the processing oil with water so that the concentration of the compound (A) is 700 ppm or more and 3000 ppm or less on a mass basis has the properties required for cutting and is used. The processing liquid can be purified by a simple purification process called filtration process.

The processing liquid for a fixed-abrasive wire saw of the present invention contains the above compound (A) and water, and the concentration of the compound (A) is 700 ppm or more and 3000 ppm or less on a mass basis, and the fixed-abrasive wire saw is used. It is characterized by being used for cutting brittle materials.

According to this configuration, it has the properties required for cutting, and the used processing liquid can be purified by a simple purification treatment called filtration treatment.

The cutting method of the present invention is characterized in that a brittle material is cut by a fixed abrasive wire saw using the above-mentioned processing liquid for a fixed abrasive wire saw.

According to this configuration, by using the above-mentioned processing liquid having the properties required for cutting processing, the cutting processing can be performed satisfactorily, and the used processing liquid generated after the cutting processing can be used. , It can be purified by a simple purification process called filtration process.

The used processing liquid treatment method of the present invention is characterized in that the used processing liquid for a fixed abrasive grain wire saw generated after the above-mentioned cutting processing method is subjected to a filtration treatment.

According to this configuration, the used processing liquid generated after the cutting process can be purified by a simple purification process called a filtration process.

Here, the properties of the processing liquid required for cutting are as follows: (1) having appropriate lubricity, (2) having high defoaming property, and (3) having high ability to suppress the reaction between silicon and water. That, (4) high wettability, and (5) high detergency can be mentioned. (1) When the lubricity of the machining fluid is low, the friction between the object to be machined and the wire increases, so that the abrasive grains are peeled off from the wire and the wire is easily broken. On the other hand, when the lubricity of the machining fluid is high, the friction between the workpiece and the wire decreases, and the wire slips against the workpiece, so that the workpiece can be cut satisfactorily. Can not. (2) When the defoaming property of the machining fluid is low, a large amount of air bubbles are generated in the machining fluid tank, so that the supply pump is in an empty suction state and the machining fluid is sufficiently supplied from the machining fluid tank to the wire saw. However, the processing accuracy is reduced. (3) When the reaction suppression ability of the machining fluid is low, the silicon chips react with the water in the machining fluid in the machining fluid tank to generate a large amount of bubbles (hydrogen gas), so that the supply pump is used. The machining accuracy is reduced because the machining fluid is not sufficiently supplied from the machining fluid tank to the wire saw due to the empty suction state. In addition, the generated hydrogen gas may explode. (4) When the wettability of the processing liquid is low, the processing liquid does not easily penetrate into the wire or the object to be processed, so that the processing accuracy is lowered. (5) When the cleaning property of the processing liquid is low, oil mud in which chips and the processing oil are mixed adheres to the processing object, and it takes a long time to clean the processing object.

In addition, the processing liquid of the present invention has a purification treatment property that it can be purified by a simple purification treatment called a filtration treatment after use. The reason why the processing liquid of the present invention has such purification treatment property is that the compound (A) contained in the processing oil agent has an appropriate balance between hydrophobicity and hydrophilicity, so that the processing generated during the cutting process is performed. It is considered that this is because it has the property of being easily adsorbed by the chips of the object.

(Processing oil)
The water-soluble processing oil for a fixed-abrasive wire saw of the present invention contains the compound (A) represented by the formula (1).
RO-[(EO) _m (PO) _n ] -H (1)
The processing oil is diluted with water so that the concentration of compound (A) is 700 ppm or more and 3000 ppm or less on a mass basis, and is used as the processing liquid for a fixed-abrasive wire saw of the present invention.

<Compound (A)>
Compound (A) is a polyoxyalkylene alkyl ether type nonionic surfactant as represented by the formula (1).

In the formula (1), R represents an alkyl group having 8 or more carbon atoms and 12 or less carbon atoms. When the carbon number of R is less than 8, the defoaming property of the processing liquid is lowered due to the increase in water solubility, and the purification treatment property is lowered. Further, when the carbon number of R is larger than 12, the solubility in the processing liquid is deteriorated, which leads to the separation of the processing liquid and the detergency is lowered. The carbon number of R is preferably 9. R may be a linear alkyl group, but is preferably a branched alkyl group. When it is a branched alkyl group, the processing liquid has higher defoaming property and wettability. Examples of R include 2-butyl-1-octyl group, 2-dodecyl group, 5-dodecyl group, 2,6,8-trimethyl-4-nonyl group, 2-methyl-4-undecyl group and 2-undecyl group. Group, 3-undecyl group, 4-undecyl group, 5-undecyl group, 6-undecyl group, 2-decyl group, 4-decyl group, 5-decyl group, 3,7-dimethyl-1-octyl group, 2, 2-Dimethyl-1-octyl group, 2-6-dimethyl-4-pentyl group, 2-methyl-3-octyl group, 6-methyl-1-octyl group, 2-nonyl group, 3-nonyl group, 4- Nonyl group, 5-nonyl group, 3,5,5-trimethyl-1-hexyl group, 2,2-dimethyl-3-hexyl group, 2,3-dimethyl-2-hexyl group, 2,5-dimethyl-2 -Hexyl group, 2,5-dimethyl-3-hexyl group, 3,4-dimethyl-3-hexyl group, 3,5-dimethyl-3-hexyl group, 2-ethyl-1-hexyl group, 2-propyl- 1-pentyl group, 3-ethyl-2-methyl-3-pentyl group, 3-methyl-3-heptyl group, ru group, 2,3,4-trimethyl-3-pentyl group, 3,4,4-trimethyl A -4-pentyl group, etc. can be used. Among these, preferably, as R, a 3,5,5-trimethyl-1-hexyl group, a 2-ethyl-1-hexyl group, or a 2-propyl-1-pentyl group can be used.

In formula (1), EO represents an oxyethylene group. Further, m indicates the average number of moles of substance added of the oxyethylene group. m is a number of 2 or more and 5 or less. When m is smaller than 2, the solubility in the processing liquid is deteriorated, which leads to the separation of the processing liquid and the chip cleaning property is deteriorated. When m is larger than 5, the defoaming property and purifying property of the processing liquid are deteriorated.

In formula (1), PO represents an oxypropylene group. Further, n indicates the average number of moles of oxypropylene group added. n is a number of 3 or more and 5 or less. When n is less than 3, the defoaming property of the processing liquid is lowered due to the increase in water solubility, and the purification treatment property is lowered. When n is larger than 5, the solubility in the processing liquid is deteriorated, which leads to the separation of the processing liquid and the detergency is deteriorated.

In the formula (1), m / (m + n) is preferably 0.33 or more and 0.625 or less, and more preferably 0.4 or more and 0.6 or less. When m / (m + n) is 0.4 or more, the processing liquid has higher detergency. When m / (m + n) is 0.6 or less, the processing liquid has higher defoaming property.

In the formula (1), EO and PO may be random addition or block addition. In the case of random addition, the working fluid has higher detergency. In the case of block addition, the processing liquid has higher defoaming property. In the case of block addition, the order of addition of EO and PO is not particularly limited.

Compound (A) can be obtained, for example, by adding an oxyethylene group and an oxypropylene group to an alcohol having 8 or more carbon atoms and 12 or less carbon atoms under an alkaline catalyst.

<Other ingredients>
The processing oil contains, in addition to compound (A), at least one of, for example, a water-soluble polymer, an antifoaming agent, a viscosity regulator, a pH regulator, an antioxidant, a fungicide, and a rust inhibitor. You may. Here, the water-soluble polymer contains at least one of a copolymer containing polyvinylpyrrolidone and a structural unit derived from vinylpyrrolidone. When the processing oil contains such a water-soluble polymer, the detergency of the processing liquid is improved. As the defoaming agent, for example, silicone oil, fluorosilicone oil and the like can be used. As the viscosity adjusting agent, for example, polyethylene glycol, glycerin and the like can be used. As the pH adjuster, various inorganic acids, organic acids, inorganic bases and organic bases can be used. As the antioxidant, for example, a phenol-based antioxidant, an amine-based antioxidant, or the like can be used. As the bactericide, for example, 1,2-benzoisothiazolin-3-one, hexahydro-1,3,5-tris (2-hydroxyethyl) -1,3,5-triazine and the like can be used. As the rust preventive, for example, alkylbenzene sulphonate, alkenyl succinic acid ester and the like can be used. The processing oil may contain water. As the water, for example, distilled water, ion-exchanged water or tap water can be used.

(Processing liquid)
The processing liquid for a fixed abrasive grain wire saw of the present invention contains compound (A) and water, and the concentration of compound (A) is 700 ppm or more and 3000 ppm or less on a mass basis. When the concentration of the compound (A) is lower than 700 ppm, the reaction suppressing ability of the processing liquid is lowered, and the lubricity and wettability are lowered. When the concentration of the compound (A) is higher than 3000 ppm, the defoaming property is lowered. The processing liquid is obtained, for example, by diluting the processing oil with water. As the water used for dilution, for example, distilled water, ion-exchanged water or tap water can be used in the same manner as the water previously contained in the processing oil.

(Cutting method)
The cutting method of the present invention uses the above-mentioned processing liquid to cut a brittle material with a fixed-abrasive wire saw. The wire used for the fixed-abrasive wire saw is preferably as thin as possible in order to reduce chips and improve the yield, and for example, the diameter is preferably 0.1 mm or less. Since the processing liquid of the present invention is highly diluted with water so that the concentration of the compound (A) is 700 ppm or more and 3000 ppm or less, it exhibits sufficient cooling ability even for thinned wires. can do. As the brittle material, for example, silicon, silicon carbide, glass, ceramic, gallium nitride or sapphire can be used, and among them, silicon can be preferably used.

(Processing liquid treatment method)
In the processing liquid treatment method of the present invention, the used processing liquid generated after the cutting processing method is subjected to filtration treatment. This makes it possible to purify the used processing liquid. That is, by performing filtration treatment, BOD (biochemical oxygen consumption), COD (chemical oxygen consumption), suspended solids (suspended solids), hexane extract (animal and vegetable oil) of the used processing liquid ) And the amount of hexane extract (mineral oil) can be reduced. As described above, the reason why the used processing liquid can be purified by performing the filtration treatment is that the compound (A) contained in the processing oil has an appropriate balance between hydrophobicity and hydrophilicity. Therefore, it is considered that this is because it has the property of being easily adsorbed by the chips of the work object generated during the cutting process. By purifying the used processing liquid to the extent that it meets the sewage exclusion standards stipulated by law by such filtration treatment, the used processing liquid can be drained to the sewer and the disposal cost is reduced. can do.

As the filtration treatment, for example, a pressure filtration treatment, a vacuum filtration treatment or a centrifugal filtration treatment can be used. Among the pressure filtration treatments, for example, a filter press treatment can be used.

Further, it is preferable that the used processing liquid is subjected to a filtration treatment and then an activated carbon treatment. By performing the activated carbon treatment, the used processing liquid can be further purified. The activated carbon treatment can be performed using, for example, a known activated carbon treatment device. Further, the activated carbon treatment may be performed by adding activated carbon to the used processing liquid after the filtration treatment, stirring the mixture, and then performing the filtration treatment again to remove the activated carbon.

(Surfactant)
Table 1 shows the surfactants used in Examples and Comparative Examples. The average number of moles of EO and PO added to each surfactant was measured by ¹ H-NMR analysis. The average molecular weight of each surfactant was measured by the GPC method (Gel Permeation Chromatography) using polyethylene glycol (PEG) as a standard polymer.

As shown in Table 2, polyvinylpyrrolidone (PVP) and an antifoaming agent were appropriately added to each surfactant to prepare a processing oil agent.

(Preparation of processing liquid)
Each processing oil was diluted with water so that the concentration of the surfactant became the value shown in Table 3 to prepare the processing liquids of Examples 1 to 15 and the processing liquids of Comparative Examples 1 to 10. In Comparative Example 10, water was used as the processing liquid.

(Dynamic friction coefficient)
A test material (silicon wafer) coated with each processing liquid is subjected to a constant load W by a test ball (silicon nitride) having a mass of 100 g, and the test material is slid at a sliding speed of 4.0 mm at room temperature. After reciprocating 20 times at / s and a sliding distance of 25 mm, the dynamic friction force P acting on the test ball was detected by a strain gauge, and the dynamic friction coefficient μ was calculated by the formula μ = P / W. Table 3 shows the measurement results of the dynamic friction coefficient.

The dynamic friction coefficient of the working liquid is preferably 0.20 or more and 0.32 or less, and more preferably 0.22 or more and 0.30 or less. When the dynamic friction coefficient of the machining fluid is 0.20 or more and 0.32 or less, it can be said that the machining fluid has appropriate lubricity. That is, when the coefficient of dynamic friction of the machining fluid is 0.20 or more, the wire saw is prevented from slipping on the object to be machined, and the object to be machined can be cut satisfactorily. Further, when the dynamic friction coefficient of the working liquid is 0.32 or less, the abrasive grains are suppressed from peeling from the wire, and the wire can be prevented from being broken.

(Maximum foam height and defoaming time)
50 ml of each processing liquid was added to a 100 ml cylinder, and the liquid temperature was adjusted to 23 ° C. Then, it was shaken 20 times and allowed to stand, and the maximum foam height and the defoaming time, that is, the time until the foam disappeared were visually measured. Table 3 shows the measurement results of the maximum foam height and defoaming time.

The maximum foam height of the processing liquid is preferably 15 ml or less, and in this case, it can be said that the processing liquid has high defoaming property. That is, when the maximum foam height of the machining fluid is 15 ml or less, the generation of bubbles in the machining fluid tank is suppressed, so that the machining fluid is sufficiently supplied from the machining fluid tank to the wire saw for machining. Accuracy can be ensured. Similarly, the defoaming time of the processing liquid is preferably 150 seconds or less, and in this case, it can be said that the processing liquid has high defoaming property.

(Amount of hydrogen generated)
40% by mass of silicon chips were added to each processing liquid, and shearing was performed with a stainless steel ball having a diameter of 2 mm at 1000 rpm for 4 hours. 15 ml of the sheared liquid was collected in a test tube having a capacity of 30 ml, and the amount of hydrogen generated was measured in a hot water bath at 50 ° C. Table 3 shows the measurement results of the amount of hydrogen generated.

The amount of hydrogen generated in the processing liquid is preferably 10 ml or less, and in this case, it can be said that the processing liquid has a high reaction suppressing ability. That is, when the amount of hydrogen generated in the processing liquid is 10 ml or less, it is possible to suppress the reaction between the silicon chips and the water in the processing liquid in the processing liquid tank to generate hydrogen gas. The liquid is sufficiently supplied from the processing liquid tank to the wire saw, and the processing accuracy can be ensured.

(Contact angle)
The angle formed by the droplets of each processing liquid dropped on the mirror-processed silicon wafer with respect to the surface of the silicon wafer was measured as the contact angle with respect to silicon. Further, the angle formed by the droplets of each processing liquid dropped on the nickel plate with respect to the surface of the nickel plate was measured as the contact angle with respect to nickel. Table 3 shows the measurement results of the contact angle with respect to silicon and the contact angle with respect to nickel. The contact angle was measured using a CA-V type contact angle meter manufactured by Kyowa Interface Science Co., Ltd.

The contact angle of the working liquid with respect to silicon is preferably 40 ° or less, and the contact angle of the working liquid with respect to nickel is preferably 50 ° or less. In this case, it can be said that the processing liquid has high wettability. That is, when the contact angle with respect to silicon is 40 ° or less and the contact angle with nickel is 50 ° or less, the processing liquid penetrates well into the nickel-plated wire or the object to be processed made of silicon. .. On the other hand, the contact angle of the processing liquid with respect to silicon is preferably 10 ° or more, and the contact angle of the processing liquid with respect to nickel is preferably 20 ° or more. In this case, the surface tension of the working liquid is not too low, and foaming of the working liquid is suppressed.

(Amount of residue adhered)
A test solution was prepared by adding 3% by mass of silicon powder (particle size: 2 μm or more and 3 μm or less) manufactured by Yamaishi Metal Co., Ltd. to each processing solution. After uniformly applying each test solution to one of two silicon wafers (polycrystal, 156 mm square), the two silicon wafers were laminated via a 0.2 mm thick spacer, and this was added to a water supply at 15 ° C. It was vertically immersed in a washing tank containing 4 liters of water and allowed to stand for 5 minutes. After pulling up the two silicon wafers from the cleaning tank and pulling the two silicon wafers apart, visually check the residue of silicon powder adhering to the surface of the silicon wafer coated with each test solution, and check the silicon wafer. The ratio of the area occupied by the silicon powder residue to the area of the entire surface of the wafer was determined. The results are shown in Table 3.

For "good", "fair", and "bad" in the "residue adhesion amount" column of Table 3, the ratio of the area occupied by the silicon powder residue to the entire surface area of the silicon wafer is 10 respectively. It means less than%, less than 50% and more than 50%. That is, when the ratio of the area occupied by the residue of the silicon powder is less than 50%, it can be said that the cleanability for the silicon wafer is high.

As can be seen from the results shown in Table 3, the processing solutions of Examples 1 to 15 containing compound (A) and water and having a concentration of compound (A) of 700 ppm or more and 3000 ppm or less have an appropriate dynamic friction coefficient. However, the maximum foam height was low, the defoaming time was short, the amount of hydrogen generated was small, the contact angle was small, and the amount of residue adhered was small. That is, the processing liquids of Examples 1 to 15 had appropriate lubricity, high defoaming property, high reaction suppressing ability, high wettability, and high detergency. As described above, the processing liquids of Examples 1 to 15 had the properties required for cutting even when the compound (A) was highly diluted to 700 ppm or more and 3000 ppm or less.

On the other hand, the processing liquids of Comparative Examples 1 and 2 in which the concentration of the compound (A) was 500 ppm had a high dynamic friction coefficient and a large amount of hydrogen generated. The processing liquid of Comparative Example 3 containing a surfactant (Sample E) having no alkyl group had a high kinetic friction coefficient, a high maximum foam height, a long defoaming time, and a large amount of residue adhered. The processing liquid of Comparative Example 4 containing the surfactant (Sample F) having a larger EO average addition mole number and PO average addition mole number than the compound (A) has a high maximum foam height and a long defoaming time. , The amount of residue attached was large. Further, in the processing liquid of Comparative Example 5 containing a defoaming agent, the maximum foam height and the defoaming time were improved, but the amount of residue adhered was large. The processing liquid of Comparative Example 6 containing a surfactant (sample G) having a larger PO average number of moles of substance than compound (A) has a high dynamic friction coefficient, a high maximum foam height, and a long defoaming time. The amount of residue adhered was large. The processing liquid of Comparative Example 7 containing a surfactant (Sample H) having no oxypropylene group had a high maximum foam height and a long defoaming time. Similarly, the processing liquids of Comparative Examples 8 to 9 containing the surfactant (Sample I) having no oxypropylene group had a high dynamic friction coefficient, a high maximum foam height, and a long defoaming time.

(Purification treatment)
The processing oil A3 and the processing oil B3 were diluted with water so that the concentration of the surfactant became the values shown in Tables 4 to 6 to prepare the processing liquids of Examples 16 to 17. Filter press processing was applied to the used processing liquid generated after cutting the silicon ingot with a fixed abrasive grain wire saw using the processing liquids of Examples 2 to 5, 9, 16, 17 and Comparative Example 5. Went. The filter press processing was performed using an RF-10B type filter press machine manufactured by Kurita Machinery Works Co., Ltd. As the filter medium, "CC34-1" (made of cotton) manufactured by Shikibo Ltd. was used. In the following, the filtrate obtained by performing a filter press treatment on the used processing liquid is referred to as a first waste liquid.

The first waste liquid was further treated with activated carbon. The activated carbon treatment was carried out by pouring the first waste liquid from above into a container filled with activated carbon and collecting the first waste liquid flowing out from below. In the following, the activated carbon-treated liquid obtained by subjecting the first waste liquid to the activated carbon treatment is referred to as a second waste liquid.

(Water quality inspection)
For the used processing liquid, the first waste liquid and the second waste liquid, the pH, BOD, COD, the amount of suspended substance, the amount of hexane extract substance (animal and vegetable oil) and the amount of hexane extract substance (mineral oil) were measured. The pH was measured based on JIS K0102 12 (glass electrode method), the BOD was measured based on JIS K0102 21 (diaphragm electrode method), and the COD was measured based on JIS K0102 17 (titration method). The amount of suspended substance, the amount of hexane-extracted substance (animal and vegetable oil) and the amount of hexane-extracted substance (mineral oil) were measured based on the method specified in Notification No. 64 of the Environment Agency of 1974. Table 4 shows the measurement results of the used processing liquid, Table 5 shows the measurement results of the first waste liquid, and Table 6 shows the measurement results of the second waste liquid.

In addition, "good" in Tables 4 to 6 means that the measured value meets the sewage exclusion standard stipulated by law, and "bad" means that the measured value does not meet the sewage exclusion standard. The sewage exclusion criteria used in this example are as follows.
pH: 5.0 or more and less than 9.0 BOD: 300 mg / l or less Suspended substance amount: 300 mg / l or less Hexane extract substance amount (animal and vegetable oil): 30 mg / l or less Hexane extract substance amount (mineral oil): 5 mg / 1 or less For COD, 50 mg / l or less was used as the evaluation standard.

As can be seen from the results shown in Tables 4 to 6, the first waste liquid obtained by performing the filter press treatment on the used processing liquid of each example is BOD, suspended solids amount and hexane extract material. The amount (mineral oil) was purified to the extent that it met the sewage exclusion criteria. The first waste liquid does not meet the sewage exclusion standard (evaluation standard) for the amount of COD and hexane extract substance (animal and vegetable oil), but the amount of COD and hexane extract substance (animal and vegetable oil) compared to the used processing liquid. ) Was reduced.

In addition, the second waste liquid obtained by performing activated carbon treatment on the first waste liquid of each example satisfies the sewage exclusion standard (evaluation standard) in terms of the amount of COD and hexane extract substance (animal and vegetable oil). Was purified up to. Therefore, the used processing liquid of each example can be drained to the sewer by performing the filter press treatment and the activated carbon treatment, and the disposal cost can be reduced.

On the other hand, in the first waste liquid obtained by performing a filter press treatment on the used processing liquid of Comparative Example 5, the BOD, the amount of suspended solids and the amount of hexane extracted substances (mineral oil) satisfy the sewage exclusion criteria. Although it was purified to a certain extent, the second waste liquid obtained by performing the activated charcoal treatment on the first waste liquid of Comparative Example 5 had COD and hexane extract substance amount (animal and vegetable oil) as sewage exclusion criteria (evaluation). Criteria) were not met. Therefore, the used processing liquid of Comparative Example 5 could not be drained to the sewer even after the filter press treatment and the activated carbon treatment.

Claims (10)

The compound (A) represented by the formula (1) is contained, and the compound (A) is contained.
Water for a fixed-abrasive wire saw, which is diluted with water so that the concentration of the compound (A) is 700 ppm or more and 3000 ppm or less on a mass basis, and is used for cutting a brittle material with a fixed-abrasive wire saw. Soluble processing oil.
RO-[(EO) _m (PO) _n ] -H (1)
(In the formula (1), R represents an alkyl group having 8 or more carbon atoms and 12 or less carbon atoms, EO represents an oxyethylene group, PO represents an oxypropylene group, m represents the average number of moles of EO added, and n is. Indicates the average number of moles of PO added, m is a number of 2 or more and 5 or less, n is a number of 3 or more and 5 or less, and EO and PO may be random addition or block addition.) The water-soluble processing oil for a fixed-abrasive wire saw according to claim 1, wherein in the formula (1), R represents an alkyl group having 9 carbon atoms. The water-soluble processing oil for a fixed-abrasive wire saw according to claim 1, wherein in the formula (1), R is a 3,5,5-trimethyl-1-hexyl group. A water-soluble polymer containing at least one of polyvinylpyrrolidone and a copolymer containing a structural unit derived from vinylpyrrolidone, an antifoaming agent, a viscosity regulator, a pH regulator, an antioxidant, a bactericidal agent, and an inhibitor. The water-soluble processing oil for a fixed abrasive grain wire saw according to any one of claims 1 to 3, further comprising a rust agent and at least one of them. It contains the compound (A) represented by the formula (1) and water.
A processing liquid for a fixed-abrasive wire saw, wherein the concentration of the compound (A) is 700 ppm or more and 3000 ppm or less on a mass basis, and the compound (A) is used for cutting a brittle material with a fixed-abrasive wire saw.
RO-[(EO) _m (PO) _n ] -H (1)
(In the formula (1), R represents an alkyl group having 8 or more carbon atoms and 12 or less carbon atoms, EO represents an oxyethylene group, PO represents an oxypropylene group, m represents the average number of moles of EO added, and n is. Indicates the average number of moles of PO added, m is a number of 2 or more and 5 or less, n is a number of 3 or more and 5 or less, and EO and PO may be random addition or block addition.) The contact angle with respect to silicon is 10 ° or more and 40 ° or less.
The contact angle with respect to nickel is 20 ° or more and 50 ° or less.
The processing liquid for a fixed abrasive grain wire saw according to claim 5 , wherein the dynamic friction coefficient is 0.20 or more and 0.32 or less. A cutting method for cutting a brittle material with a fixed-abrasive wire saw using the processing liquid for a fixed-abrasive wire saw according to claim 5 or 6 . The cutting method according to claim 7 , wherein the brittle material is any one of silicon, silicon carbide, glass, ceramics, gallium nitride and sapphire. A used processing liquid treatment method, which comprises performing a filtration treatment on the used processing liquid for a fixed abrasive grain wire saw generated after the cutting processing method according to claim 7 or 8 . The used processing liquid treatment method according to claim 9 , wherein the used processing liquid for a fixed abrasive grain wire saw is subjected to the filtration treatment and then the activated carbon treatment.